fix(deploy): drop broken migrate service, add defaults for missing env vars

migrate service used TypeScript source not available in standalone image.
Migrations must be run separately (pnpm db:migrate against prod DB).
Added defaults: POSTGRES_DB=epicure, POSTGRES_USER=epicure, MINIO_ROOT_USER=minioadmin.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

docker/compose.prod.yml

@@ -3,8 +3,8 @@ services:
     image: postgres:17-alpine
     restart: unless-stopped
     environment:
-      POSTGRES_DB: ${POSTGRES_DB}
-      POSTGRES_USER: ${POSTGRES_USER}
+      POSTGRES_DB: ${POSTGRES_DB:-epicure}
+      POSTGRES_USER: ${POSTGRES_USER:-epicure}
       POSTGRES_PASSWORD: ${POSTGRES_PASSWORD}
     volumes:
       - postgres_data:/var/lib/postgresql/data
@@ -36,7 +36,7 @@ services:
     image: minio/minio:latest
     restart: unless-stopped
     environment:
-      MINIO_ROOT_USER: ${MINIO_ROOT_USER}
+      MINIO_ROOT_USER: ${MINIO_ROOT_USER:-minioadmin}
       MINIO_ROOT_PASSWORD: ${MINIO_ROOT_PASSWORD}
     volumes:
       - minio_data:/data
@@ -50,28 +50,16 @@ services:
     networks:
       - internal
 
-  migrate:
-    image: epicure-web:latest
-    command: ["node", "-e", "import('@epicure/db').then(m => m.migrate())"]
-    environment:
-      DATABASE_URL: postgresql://${POSTGRES_USER}:${POSTGRES_PASSWORD}@postgres:5432/${POSTGRES_DB}
-    depends_on:
-      postgres:
-        condition: service_healthy
-    restart: on-failure
-    networks:
-      - internal
-
   web:
     image: epicure-web:latest
     restart: unless-stopped
     ports:
       - "${APP_PORT:-3000}:3000"
     environment:
-      DATABASE_URL: postgresql://${POSTGRES_USER}:${POSTGRES_PASSWORD}@postgres:5432/${POSTGRES_DB}
+      DATABASE_URL: postgresql://${POSTGRES_USER:-epicure}:${POSTGRES_PASSWORD}@postgres:5432/${POSTGRES_DB:-epicure}
       REDIS_URL: redis://:${REDIS_PASSWORD}@redis:6379
       STORAGE_ENDPOINT: http://minio:9000
-      STORAGE_ACCESS_KEY: ${MINIO_ROOT_USER}
+      STORAGE_ACCESS_KEY: ${MINIO_ROOT_USER:-minioadmin}
       STORAGE_SECRET_KEY: ${MINIO_ROOT_PASSWORD}
       STORAGE_BUCKET: epicure-uploads
       BETTER_AUTH_SECRET: ${BETTER_AUTH_SECRET}
@@ -86,8 +74,6 @@ services:
         condition: service_healthy
       minio:
         condition: service_healthy
-      migrate:
-        condition: service_completed_successfully
     networks:
       - internal